Effects of Nutrient Intake and Exercise on Bone Mineral Density and Bone Mineral Density in Premenopausal Women

This study investigated associations between calcium intake, exercise behaviors, lumbar bona mineral density (BMD), and bone mineral content (BMC) among 79 premenopausal women (mean age = 41yr). The BMD and BMC of the lumbar spine (L$_2$-L$_4$) were measured by dual energy x-ray absorptiometry. Nutrient intake was estimated by the convenient method and a quantitative food frequency questionnaire was designed for this study that included the most commonly consumed floods sources of Ca. Participants were asked to identify all activities of exercise they had participated in including estimation of number of years of participation, number of weeks per year, number of times per week, and the number of hours per session. Participants were then categorized into the exercise group or nonexercise group (control). To meet the criteria for inclusion in the exercise group, the subjects participated more than 3 sessions per week and more than 30 minutes per session and the length of the exercise participation was at least more then 6 months. The participants were also grouped by calcium intake. The total calcium intake of all participants was estimated by dietary calcium intake and then the subjects were divided into quartiles to assess the lumbar BMD and BMC of the upper 25% (average calcium intake = 910 mg) and the lower 25% (average calcium intake = 414 mg). Results indicated that there were no significant differences in energy and calcium intake, and that there were no significant differences in lumbar BMD and BMC between participants in exercise group and the nonexercising control group. However, the exercise group had significantly lower ALP concentration than the nonexercise group. The upper 25% calcium intake group had significantly greater lumbar bone mineral density and bone mineral content than the lower 25% calcium intake group. Also the upper 25% calcium intake group had significantly lower ALP concentration than the lower 25% calcium intake group. Correlation analysis revealed that the spinal BMB was positively associated with body weight, while calcium intake was negatively associated with ALP concentration in nonexercising women. However, neither body weight nor dietary calcium intake were associated with both spinal BMD or ALP concentration in exercising women. These results suggest that calcium intake positively influence bone mineral density and bone mineral content in nonexercisulg premenopausal women. Exercise group did not affected by body weight and dietary calcium, but decreased ALP concentration than nonexercising group. Both exercise and calcium intake positively influence bone mineral density and bone mineral content in premenopausal women.

폐경 전 성인여성에서 영양섭취 상태와 운동이 골밀도 및 골무기질 함량에 미치는 영향

본 연구에서는 골다공증의 예방 차원에서 골밀도와 영양소 섭취 상태 및 운동과의 상관성을 조사하기 위하여 대구 지역 성인 여성 74명을 대상으로 간이식이 조사법과 면접 및 설문지를 이용하여 영양소 섭취 량과 운동량 등을 조사하였으며 이중에너지 방사선 골밀도 측정기 (DEXA)를 이용하여 척추 골밀도를 측정한 연구 결과를 요약하면 아래와 같다. 1) 운동군과 비운동군의 각각 에너지 섭취량은 1,921 kcal와 1,733 kcal였고, 평균 일일 칼슘 섭취 량은 각각 652 mg과 635 mg으로 두 군간에 유의적인 차이가 없었다. 2) 운동군과 비운동군은 각각 골밀도가 1.16 g $\pm$0.11/$\textrm{cm}^2$, 1.14 g = 0.14$\textrm{cm}^2$이었고, 골무기질 함량 은 각각 49.6 g $\pm$ 7.8, 47.4 g $\pm$ 9.3으로 두 군간에 유의적 인 차이가 없었다. 3) Alkaline phosphatese (ALP)는 운동군이, 비운동군 보다 유의적으로 낮았다 (p < .05) 비운동군에서는 연령과 ALP가 양의 상관관계가 보였으나 운동군에서는 상관성이 없었다. 4) 칼슘 섭취수준에 따라 낮은 25%군과 높은 25%군을 비교하였을 때 높은 25%군의 골밀도는 낮은 25%군 보다 높은 경향을 보였고 골함량은 유의적으로 높았다. 5) ALP는 칼슘섭취가 낮은 25%군이 칼슘섭취가 높은 25%군보다 유의적으로 높게 나타났다.